Grease stick



Patented Jan. 26, 1943 GREASE STICK Marcellus T. Flaxman, Inglewood, Califi, assignor to Union Oil Company of .California, Les 7 Angelcs, Calif., a corporation of California N Drawing.

Claims.

This invention relates to hard lubricating greases, particularly to those which may be molded in stick form to be adapted for such uses as the lubrication of latches and hinges of automobile doors and the like.

The principal object of the invention is to furnish a grease composition suitable for the formation of such lubricating sticks, which composition will have a sufiiciently hard body, will be tough but not brittle, and will spread evenly and uniformly during application with ood continuous adhesion and without the formation of uneven or broken films or layers, and yet be free from undue softness.

The invention resides in the employment of substantially oil-free paraffin wax as the principal or body-forming constituent, to which has been added a quantity of substantially oil-free petrolatum as a toughening agent, together with a quantity of carnauba wax to impart adequate hardness, and with the further addition of a quantity of tallow which is necessary to reduce brittleness of thegrease stick, especially at lower temperatures and also to supply the characteristic of uniform adhesion and production of a smooth uniform layer of the grease upon application to the parts to be lubricated. Preferably, there is also added a quantity of lanolin which especially controls or modifies the crystalline character of the paraffin wax and partially overcomes brittleness Im this respect the lanolin may be considered as a sort of binder or agent to improve compatibility; However, the lanolin may be omitted where a stick of best quality is not required.

In the practice of the invention a paraflin wax of around 135 F. melting point is employed to constitute roughly one half of the composition. Thus, it may be" considered as constituting the grease body, or as a filler or as a carrier for the other constituents. The petrolatum, the tallow and the lanolin are used in minor proportions in the order of 15% to 20% each, the petrolatum and the tallow, especially the petrolatum, being increased to or perhaps slightly above the larger limit indicated where the lanolin is not employed. The carnauba wax is added normally in a still smaller proportion suiiicient to impart the desired hardness. This might vary from 5% to perhaps 8% being a general average. In selecting petrolatum, it is desired that it be as free from oil as possible. A substantially oil-freepetrolatum is now obtainable on the. market un- Application December 15, 1941, Serial No. 423,035

der the name Petrowax A produced by the Gulf Oil Corporation. In selecting tallow and grease or degras.

Approx- By weight imato range Per cent Per cent North Country carnauba wax 8. 5 Ho 10 Paraifin wax 135437 F. melting point 42. 5 to 40 Lanolin U. S. P. anhydrous 17.0 15 to 20 Pctrolatum (Petrowax A") 17. 0 15 to 25 Edible tallow 15.0 15 to 20 The melting point of the paraffin may vary, for example, from F. to 170 F.

A specific suitable composition free from the lanolin is as follows:

Approx- By weight imate range Per cent Per cent Carnauba wax 5 5 to 10 Parafiin wax F. melting point 50 60 to 40 Petrolatum 25 15 to 25 Edible tallow 20 15 to 25 In preparing a batch of grease suitable forthe formation of pieces, bricks or sticks, the above constituents in the amounts indicated are melted together. For example, all of the stated ingredients may be charged into a steam-jacketed kettle and melted at any appropriate temperature in the order of 180 F'. to 220 F. The mass is thoroughly mixed as by agitating with paddles to secure uniformity of distribution and consistency. A temperature of 180 F. is adequate to secure a good melt and mixture, whereas 220 F. is not hot enough to alter the nature of any of the ingredients. When the batch has been melted and thoroughly commingled, it is carefully and uniformly cooled to avoid local chilling and insure uniformity of the product, the temperature being brought down to'-a drawing temperature of from about F. to about 1'70"v F. At the time of drawing all of the batch is to be in liquid condition. The product is then drawn while maintaining said temperature and while continuing agitation The product may be drawn directly into tubes or other molds. Or the product may be drawninto trays for the formation of slabs and cooled under conditions such as to prevent any tendency to stratification of low and high melting materials.

Grease sticks produced as above indicated possess the requirements of sufflcient hardness and toughness without brittleness, and have the capacity to spread smoothly and effect uniform distribution of the lubricant which is most desirable especially for manual application to small surfaces.

Variation in the percentages maybe made, especially within the limits indicated, so long as the required physical characteristics above indicated are obtained. In the preferred form lanolin, or'wool grease, is employed in order to insure the most uniform and unctuous product, but may be omitted where the improved homogeneity and crystallization control imparted by lanolin are 'not required.

I claim:

1. A grease composition comprising a major proportionof paraffin wax, and minor proportions of carnauba wax, petrolatum substantially free from oil, and tallow in proportion to yield a hard, tough, non-brittle stick capable of being applied to form a smooth coating possessing the characteristics of uniform and even adhesion to surfaces being lubricated.

2. A grease according to claim 1 containing also a minor proportion of wool grease to modify the crystal structure of the paraffin and impart homogeneity to the composition. 7

3. A grease composition according to claim 1 wherein the paraffin wax is present in the order of one half of the composition, the carnauba wax is present in the order of one tenth of the com position and thetallow and petrolatum are present in the order of 15% to 20% of the composition.

4. A grease composition comprising paraffin wax in the order of 40% to of the composition, carnauba wax in the order of 5% to 10% of the composition, and wool grease, petrolatum and tallow each of which is present in the order of 15% to 20% of the composition.

5. A grease according to claim 4 wherein the wool grease is in the form of lanolin and the tallow is an edible grade.

MARCELLUS T. FLAIQVIAN. 

